1. Field of the Invention
The present invention relates to a backlight module of display device, and in particular to a backlight module of a display device that ensures completeness of reflected light and also improves heat conduction performance of backlight source.
2. The Related Arts
An LED (Light-Emitting Diode) backlight module is generally classified as two types according to the position of light source, namely direct type and edge type. In backlighting of direct type, the light source is located exactly below an LCD (Liquid Crystal Display) panel for direct irradiation. Since it is possible to use a large number of light tubes, extremely high brightness can be realized. However, the cost is high and this makes generally available for TV modules that require great brightness. Backlighting of edge type positions a light source at an edge of a light guide plate and light from the light source is guided into the interior of the light guide plate to be subjected to total reflection by a reflection surface and refraction caused by grid spots on a bottom of the light guide plate in order to emit from a top surface of the light guide plate to serve as a planar light source of homogenous brightness for the LCD panel.
The state-of-the-art edge type backlighting comprises a planar mirror that is directly mounted to a plastic frame or a back panel and the commonly adopted way is to mount manually. Manually mounting may cause a problem in yield rate, and thus affecting reflection of LED light and lowering light emission efficiency.
Further, heat dissipation is another issue of backlight modules that requires constant improvement.